Process of making vanillin.



PATENTBD JAN. 22, 1907. E.4 L. FROGER-DELAPIBRRE. PROCESS 0F MAKING VANILLIN.

APPLIOATIONHLBD JUNE 26.1902.

2 SHEETS-SHEET 1.V A

No. 841,957. PATBNTBD JAN. 22, 1907.

- E. L. PRoGER-DELAPIBRRE.

PROCESS 0F MAKING VANILLIN. APPLICATION FILED JUNE 26.1902.

z SHEETS-SHEET 2.

ma e use of to xidize, for instance, the

allyl group GHZ-CH--CH2 of eugenol or the `propenyl group l CH3-CIl---CII of isoeugenoh The sameiwould be the case with the lUNITED STATESl PATENT. OFFICE.

EDOUARD LOUIS Fao'eria-DELAPTEses` or COURBEVOIE, FRANCE.

PROCESS o|= viAKlNe VANILLIN. l

Specifica?y f of Letters Pailit.

Patented Jan. 22, 1907.

` Application filed June 26,1902. Serial Nar lj.3,270.

L To a/ZZwvwm, it may concern,.-

' phenol groups.

A. Be it known that I, EDOUARD Louis FRO- erin-DnLAPIERRE, chemistpof 2x5 Rue de Belfort, Courbevoie, Seine, Re ublic of France, have invented a new and mproved Process for the Production of Aromatic Aly dehydes Containing Free Phenol Groups, of which the following is a full, clear, and exact description. 'A f l The present invention has for its obj-et a process for the production of vaniliin: 'or other aromatic aldehydes containing free The new process is based uponthe oxi-l dizing action exerted-Byoxygen in presence.

of terpins, ses uiterpins, .&c., upon phenols containing ally groups or propenyl groups, or upon certain erivatives of such phenols with free phenol groups, such ascloveoil, euoenol, isoeu genol, and their analogues.

t is a Well-knownfact that tery ins and their analogues have the property o 4activatnl ing or energizin oxy en and transferring it in this form-tot e bo ies to'be oxidized. In

the resent invention, then, this propertyT is other analogous compounds.

The process differs from other similar ones pro osed for "analogous purposes in that Whl e with the latter the oxygen is used. in theshape of ozone this is not the case here., since' itis known that the terpins, &c., do not convert oxg'yep ipto the form of ozone, Whose presence'is rather excluded, because it cannot exist in presence of terpin-vapors By substituting oxygen energized or activated by'terpins, &c., for ozone the advanta e is obtained thatthe oxidation sto s with t 1e conversion of the allyl group or tiie propenyl group into the aldeliyde group,

v tion to obtain the desired aldehyde.

While with other processes when the reaction has advanced to a certain percentage oi aldehyde formation tliere is a further action,

with partial resiuication. This resinification it was heretofore possible to prevent only by introducing before the oxidation certain substituents into the phenol groupforinstance, by first producing a sulphethylic acid. Naturally these substituents have to be separated out again after theoxida- In the present process, however, it is perfectly immaterial whether theV phenol group is blocked or not, and it is therefore notnecessary to start with blocked phenols in the oxidation. Hence the tedious and costly intermediate reactions .mentioned are avoided and in spite thereof materially higher yields of' aldehydes are obtained, owing to the avoidance of resiniiication. Moreover, the purity of the starting materials is not of ab solute necessity with the present process. The reaction takes place in all cases according to one of the following equations:

ons

Accordingly there results movement ofthe va ors is of course efected by means' of a puri ed dry or moist current of air.

As a practical example the production of vanillin according to the present invention is described below.

Acurrent of air freed from nitrous combinations and carbonio acid is passed through oil of turpentine,'\which, according tothe degree of viscosity,`has been heated to 30 to 35 centigrade. Next the current' is conducted through a suitable column, kept at 80 to 90 centigrade with heated plates, against which the fumes strike, and then over a flat layer of isoeugenol maintained at about 100 centigrade. The speed is one hundred and twenty-five liters of effective air per hour, and the length of the operation is governed by the quantity of vanillin to be produced, which may be up to fortytwo per cent. for the first treatment. The isolation of vanillin can be effected as usual with the aid of the bisulfite compound. For the oxidation of compounds containingr the allyl group the same process may be used. It has been found advantageous, however, to use in place of air a mixture (free from nitrogen) of oxygen one-third and carbonio anhydrid two-thirds. It is also well in this case to have the compound to be oxidized neutral sam, Burgundy' pitch, residues from the distillation of turpentine, certainV resins` &c. 'lhey may be used alone or in suitable solution or else mixed With Water.

Having thus described' my invention, I claim as new and desire to secure by Letters Patent The method herein described` of 1nanuiiac-l turing;r vanillin and similar aromatic aldeh vdes containing a free phenol group, which consistsin subjectingr bivalent phenols tothe action of oxygen in the presence of terpins as described'.

The toregroinzgr specification of my improved process for the manufacture of vanillin and vother analogous bodies sig-ned by me this. 5th

day of June, 1902.

EDOUARD Louis FiioGER-DELAPIERRE. [as] l 'Titiicsses: i

SnuEoN HoNoR MARIE CRELB, (WIARLES ADoLPHE FELKER. 

